1. Field of the Invention
The present invention pertains to thermal batteries
2. Description of the Prior Art
Thermal batteries are used in mines, missiles, torpedos, laser target designators and depth charges. Thermal batteries are used to provide energy to operate fuzing devices and guidance and control devices. These applications usually do not require long lasting batteries; and an operating time of about one to three minutes is sufficient for short range missiles, while a medium to long range missile might require an operating time of about fifteen minutes.
Prior art thermal batteries require internal temperatures from about 450.degree. C. to 550.degree. C. in order to operate. It has proven difficult to maintain the required internal temperature for the desired operating time; and prior art thermal batteries operate only within narrow temperature ranges, typically about 100.degree. C. If the temperature is too low, the electrolyte freezes; and the battery ceases to function. If the temperature is too high, the oxidizer is quickly depleted, causing the battery to cease functioning.
A further difficulty with prior art thermal batteries is that the high operating temperatures preclude their use in close proximity to human beings.